This appears to normally use the move constructor, but on Jenkins Fedora
20, it tried to use the copy ctor, which is deleted.
Constructing directly fixes this, and is the right way, anyway.
This compares the performance of RICHIO line readers against other
implementations, and can be used for profiling and optimisation.
Current benchmarks provided:
* richio FILE_LINE_READER
* Raw std::ifstream (no LINE_READER wrapper), using getline (so no line
length limiting)
* LINE_READER wrapper around std::istream, with a std::ifstream
implementation
* Existing richio wxInputStream wrappers (with File and FFile
implemntations)